helper: fix minor typos

Change-Id: I785e388148c0329e51cb0b39ab30e8ee44f5a7cd
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/5801
Tested-by: jenkins

src/helper/bin2char.sh

@@ -4,7 +4,7 @@
     echo "Usage: $0"
     echo
     echo "Read binary data from standard input and write it as a comma separated"
-    echo "list of hexadecimal byte values to standard ouput. The output is usable"
+    echo "list of hexadecimal byte values to standard output. The output is usable"
     echo "as a C array initializer. It is terminated with a comma so it can be"
     echo "continued e.g. for zero termination."
     exit 1